If we take a closer look at the order in which things took place in DF and now in DFC in regards to the White Lady, perhaps we can see things a bit more clearly. So this is simply to sum things up:
- Zoë encounters Faith, or rather an image of Faith early on in the game. Faith tells her to find and save April. Given the events at the end of DF, it appears that it was the White Lady who instructed Faith to do so. So apparently at the beginning of DF the White Lady was already in contact with Faith and apparently she could contact Faith but not Zoë directly.
- Later on in DF, April meets the White Kin. As mentioned, many of us believe she is the same as the White Lady. The White Kin mentions nothing to April about her needing to be saved. Remarkable, but possible.
- Some time after that, Zoë meets the White Kin and indeed, she is now directly being instructed by the White Kin to at least go where she is needed the most and she ends up at the rebel camp where we can only assume that she somehow manages to save April, because after this she once more ends up with Faith.
- Before Zoë ends up with Faith again, but after Zoë has talked to the White Kin, the White Kin is attacked. We don't know what happens to her.
- Faith then tells Zoë that according to the White Lady April has been saved, which means that after Zoë has met with the White Kin, the White Kin/White Lady has contacted Faith.
- Then we get to Saga as a baby. Granted, we do not know if these events take place before, during or after any of the events in TLJ, DF and/or DFC, but due to the order of the games, I will put this event at the end of the list. The White Lady talks to Saga and that is the last we see of her. For now, at least.
One thing that stands out to me immediately after summing this up is that apparently the White Lady was already able to contact Faith before she was attacked and possibly killed, since from the beginning of DF Faith is telling Zoë to find and save April. The theory that the White Lady/the White Kin can only visit Faith after she has been attacked/killed at the library does not seem to stick, then.
And if indeed Saga's story does take place after the events in DF (but not necessarily those in DFC) and if Saga is somehow April reincarnated, the way the White Lady talks to Saga does seem to make sense, more or less, at least to me.
Reading it like that, an image arrived in my head of a new way of looking at the Divide: Perhaps it's not just magic and technology in the sense we think, but rather that in however it was created, space-time was warped, and Arcadia is actually the past, with Stark the future. The HoaW could be the present, or at least some way that time is bridged. Of course it's likely wrong. There's little hint to suggest anything about space-time being involved in the story, outside of Brian being trapped for so long between worlds. It's just an image that flashed into my head, and so thought I'd share.
As for the whole Zoe saving April: I have always wondered about this, but since playing through again, I'm wondering if it's something to do with how she speaks to Kian, though I can't see how Zoe influenced that. The only other theory I have is that Zoe saved her simply by witnessing her ''death'' and thus making it a part of her own reality/truth. Had she not seen it and headed back to Stark instead, April's fate would have been unknown to her. I feel this is significant.
Though it could just as easily not be.